Tracking indoor pedestrian using Cricket indoor location system

The Cricket mote is a ranging system that uses Time Difference of Arrival between an ultrasonic and a radio signature to locate the position of a device with an error of a few centimeters. In this paper we propose the design and implementation of the Cricket-based indoor location system to track indoor pedestrian with low latency. Our results show the system is able to track an indoor pedestrian walking at a speed of 1.28 m/s in a room of 190 m2 with 50 cm accuracy with less than 50 milliseconds latency. Our results also show the impact of human body shadow effect on the ultrasonic signal system. The improvement in tracking performance is obvious when body shadow effect is reduced or eliminated.